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At public events, when the national anthem reaches “O’er the land of the free,” the music swells and everyone sings or cheers. We think of ourselves as free-spirited, fiercely independent, enterprising and innovative, which harkens back to self-reliant family homesteads in the era of the pioneers.
However, during the 19th and 20th centuries, we sought the best of both worlds. We retained our family cocoons while improving our quality of life by organizing society in villages, towns and cities. They became connected within and to each other so we could more efficiently benefit from sharing roads, bridges, agricultural co-operatives, electricity and water systems. We developed institutions such as schools, hospitals, community centers and governments tasked with managing these assets and establishing fairness and order.
One hundred or more years on, it seems time for a review. Infrastructure is outdated, crumbling and expensive to maintain. Some of the big centralized systems, structures and organizations have begun defeating their own purposes, creating bureaucratic inefficiency rather than economies of scale. Political leadership positions are now careers rather than callings, with too many monetary influences on policy.
The effects of climate change, and air and water pollution are raging, and technologies that we rely on too heavily are threatening the health of our families and of the planet. Everything we’ve built in the last couple of centuries is now in the spotlight. What’s working? What isn’t?
Fortunately, our enterprising and innovative nature has allowed us to develop and test alternative approaches. A high level of invention has emerged, and with so many new options for energy, transportation, buildings, industry and agriculture, we enjoy increasing flexibility at a time when we need it.
In the construction business, some recent trends in the land of the free suggest a move back to smaller, more self-reliant communities, buildings and energy models, although many of us want to keep our options open and also enjoy connections to larger networks.
Basalt Vista Microgrid
The Basalt Vista Affordable Housing Community is a 27-home, deed-restricted neighborhood located a few hours west of Denver. The Basalt High School donated the land for the project, which was built by Habitat for Humanity with support from local governments, national agencies and technology companies.
Deed-restricted means that because public money helped keep purchase prices much lower than typical in the area (a few hundred thousand compared with more than $1 million dollars), properties can only be sold for a few percentage points more. This prevents property speculation and ensures available, affordable housing in remote communities for, in this case, school teachers, ambulance drivers and other public employees.
The last duplex was completed this summer; all 27 units are already occupied.
The 2- to 4-bedroom duplex and triplex homes are net-zero — meaning electrified with solar panels on the roofs, lithium-iron-phosphate batteries from Blue Planet Energy, efficient appliances, tight building envelopes, more insulation, Carrier mini-split heat pumps, RenewAire energy recovery ventilators (ERVs) and
A. O. Smith heat pump water heaters.
Thanks to solar on the rooftops and sophisticated power-sharing technology, each home generates more electricity than it uses.
So far, utility bills are about 85% lower than typical electric bills in the state, notes architect Erica Golden from the 2757 Design Co., which designed the homes. She says homeowners often pay only the required monthly minimum of about $12 for power. This is made possible partly through the use of smart controllers from Heila Technologies. They optimize efficiency of the photovoltaic panels, batteries, electric vehicle charging, heating and cooling.
Golden points out that the Basalt Vista system can “island” off from the Colorado grid to avoid brownouts during extreme weather or wildfire problems. When in island mode, the neighborhood draws its power from battery storage and the rooftop solar.
Autonomous Energy Grid Challenge
For some communities and utility grid operators, this amazing flexibility has been easier said than done. The Department of Energy’s National Renewable Energy Laboratory used the first four homes built in the Basalt Vista project as a pilot. The goal was to study artificial intelligence and algorithms and the integration of national grids and distributed energy resources: microgrids, renewables and batteries.
The lab has been proving out standardized models to help prepare for a future in which electrified buildings and vehicles will become the norm.
It will be formidable and complicated because every year for at least the next 30 years, residential solar installations are expected to grow by about 8%. Household battery systems could reach a total of 1.8 gigawatts by 2025.
And around 8.7 million electric vehicles could be on U.S. roads by 2030.
A sheer volume of diverse computational challenges must be successfully executed in fractions of one second. And still, there is uncertainty. Examples include fluctuating wind speeds, cloud and snow cover, storms and wildfires leading to evacuations, power market volatility, time of use charges, sudden connections of large communities, corporate or institutional campuses, and so on.
For example, by 2030, the utility plans to install a 150-megawatt, solar-powered summer peaking system in the Basalt Vista community.
Operators know a centrally controlled grid can’t handle coordination in the face of huge volumes of devices and resources. Instead, they will need to manage a system of distributed optimization. Before giving up control, they must develop and establish universal standards for compliance by the diverse players who will become involved.
Texas Grid Woes
Modern grid development may be progressing smoothly in Colorado, but in Texas, not so much. Some misinformation has been spread about what caused the catastrophic system failure during the 2021 cold snap and difficulties during the heat wave in July of this year. I decided to visit the state and consult with a true expert, Scott Hinson, chief technical officer of Pecan Street, a grid research and consulting firm in Austin.
For the past 10 years, this nonprofit conducted numerous practical research pilots for utilities, governments and other organizations. For example, it studies vehicle-to-grid models and installs energy-monitoring devices to measure every circuit in homes at one-second intervals, collecting and analyzing about 10.5 million data points per day.
“In 2021, gas, coal and nuclear power all had issues because sensing equipment was not winterized,” Hinson says. “Some gas well heads froze and some other things went wrong; natural gas power production plummeted, causing the outages. This was not caused by renewables.
“People say the system has been improved for 2022, and I know that in some cases, they filed weatherizing plans, but only a few have implemented them. The empirical evidence is overwhelming that these statistically improbable extreme weather events are now happening with far too much regularity and are caused by climate change.”
Texas may be big and slow, but it is progressive; it is the top wind-power-generating state in the country. And in 2021, it added 6060 MW and became the fastest-growing solar market, according to the Solar Energy Industries Association (15% increase in community and commercial, 86% increase in utility-scale solar farms).
Hinson shed some light on some of the complexities involving home electrification: “The way homes use energy is far more dynamic than we thought. The usage curves show that houses go from 3 kilowatts to
11 kilowatts in one second as air conditioners or clothes dryers turn on or off, or clouds arrive to reduce solar energy collection. The peak load of a house can be 12 times as much as its average load. It makes it challenging to manage.”
He adds: “Through algorithms and planning, you can flatten out that curve. For example, scheduling car charging or laundry at the right times during the day. So, in general, the cooktop is what rules the roost (as least flexible) because when you're hungry, you often cook.”
When I began writing about clean energy in homes about 20 years ago, it really meant a costly heat pump that only solved some small part of a larger space-heating challenge. Today, we want homes to be 100% optionally self-contained during exceptional events, plus connected to the grid to access cheap energy when optimal, working seamlessly with batteries and solar.
All this while achieving low operating costs, low energy consumption, low greenhouse gas emissions and high-quality indoor air.
We are now talking about heat pumps, ERVs, heat pump water heaters, induction cooktops, drain water heat recovery, rainwater collection and electric car chargers. Different climate conditions, building forms, local ordinances and project characteristics also contribute complexity. Ideally, we start with well-sealed, super-insulated building envelopes, which make these goals much easier to meet.
Years ago, John Sarter and his design-build firm, Off The Grid Design, began researching in Japan and elsewhere, connecting the dots between solar and clean heating, cooling, ventilating, cooking and charging. It seemed logical to him that a larger structure with a lower ratio of internal volume-to-surface area would be a more economical model for a Passive House certified and fully electric building.
He developed Sol Lux Alpha, a six-story building in San Francisco, with four 1,800-square-foot, three-bedroom condominium apartments stacked between a parking garage and an outdoor roof deck at the top. Each apartment includes two ducted mini-split coils for heating and cooling, ERVs, heat pump water heaters, and all-electric kitchens with induction cooktops.
The ERVs mean excellent indoor air quality. Heating and cooling are provided only in the four apartments, which are Passive House-certified, built using prefab structural insulated panels, with careful attention to perforation elimination, tight assembly and uncompromised sealing. They’re very quiet inside; Sarter says the extensive use of electrification still does not create a huge power load.
Electricity for 100% of the four condos plus electric car charging in the garage is covered by renewable energy from the solar PV system above the building’s roof deck, three Tesla batteries in each condo, plus some batteries for the common areas. Any excess power during the year can be paid back from San Francisco’s Clean Power excess generation tariff at $.089/kWh. “We even wired it for vehicle-to-grid in case they want to do that in the future,” Sarter says.
The shared roof deck includes an outdoor kitchen, and dining and lounge areas; it is bathed in filtered sunlight through the bifacial solar panels. Bifacial boosts the
380 W nominal output by up to 30% to almost 500 W per panel. Each unit’s batteries store up to 41.5 kWh, which can power a condominium for two to three days without recharging due to the efficiency of the building’s systems. The common areas and elevator are powered by a separate set of batteries capable of storing 24 kWh. They provide commercial-grade, three-phase power for the elevator through a triple-inverter configuration.
Because the PV is recharging the batteries all day, condo units can potentially run off-grid indefinitely. As a test, the entire unoccupied building ran off-grid for over three weeks during construction and generated substantial excess energy each day. The units sold very quickly; three of the owners own electric cars.
Owners can set it and forget it or customize the way the energy storage system interacts with the grid. Each unit is separately metered and each owner can take advantage of time-of-use rates and EV tariffs in their own ways.
Passive House consultant Graham Irwin says that isolating the apartments from the unconditioned podium garage level, elevator, foyer and roof deck was a bit tricky at times.
“The roof deck is very pleasant with the panels providing translucent shade and rain protection,” he explains. “They have cookouts up there at all different times of the year. As for the condo units, heating happens when solar energy is minimal, so it is an enormous benefit having a very efficient envelope and small heating loads because the shell retains energy and the building itself acts like a battery.”
Irwin adds: “Along with actual lithium batteries, it becomes easy to coast through periods of peak demand for days at a time. I think this will become more clearly advantageous as we move forward, and I don’t know why anyone would build any other way at this point.”
Sol Lux Alpha overcame some challenges with prefab panels and battery suppliers. It was completed in 2018, won some awards and gave the development team confidence in their model. Their companies are continuing to work on Passive House and microgrid projects. Building science experts and industry professionals have traveled from Switzerland, Australia and elsewhere to visit and learn about the project.
All across this continent, modern projects demonstrate that we can create buildings and communities with the autonomy they need and want while still connecting to the main grid. It helps solve high energy costs, climate change, the expensive crumbling of old infrastructure, healthy refuge during pandemic cocooning, electrified cars and smarter homes.
Perhaps most importantly, it allows Americans to revert to the self-reliant homesteads of the past and our cherished cultural identity. Sing it out. Sing it proud. It’s the land of the free.
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